//
//  UIImage+Category.m
//  ESport
//
//  Created by mac  on 14-11-21.
//  Copyright (c) 2014年 kdong. All rights reserved.
//

#import "UIImage+Category.h"

@implementation UIImage (Category)

+ (UIImage *)strechingWithImageName:(NSString *)imageName
{
    UIImage *image = [UIImage imageNamed:imageName];
    image = [image stretchableImageWithLeftCapWidth:image.size.width * 0.5 topCapHeight:image.size.height * 0.5];
    return image;
}

//- (UIImage *)scaleWithImage:(UIImage *)image
//{
//    UIGraphicsBeginImageContext(CGSizeMake(image.size.width * 0.5, image.size.height * 0.5));
//    // 绘制改变大小的图片
//    [image drawInRect:CGRectMake(0, 0, image.size.width * 0.5, image.size.height * 0.5)];
//    // 从当前context中创建一个改变大小后的图片
//    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();
//    // 使当前的context出堆栈
//    UIGraphicsEndImageContext();
//    // 返回新的改变大小后的图片
//    return scaledImage;
//}

+ (UIImage *)scaleFromImage:(UIImage*)image scaledToWidth:(CGFloat)newWidth
{
    CGSize imageSize = image.size;
    CGFloat width = imageSize.width;
    CGFloat height = imageSize.height;
    
    if (width<newWidth){
        return image;
    }
    
    CGFloat widthFactor = newWidth / width;
    
    CGFloat scaledWidth = newWidth;
    CGFloat scaledHeight = height * widthFactor;
    CGSize targetSize = CGSizeMake(scaledWidth,scaledHeight);
    
    UIGraphicsBeginImageContext(targetSize);
    [image drawInRect:CGRectMake(0,0,scaledWidth,scaledHeight)];
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
}


+ (UIImage *)scaleShareImageFromImage:(UIImage*)image scaledToWidth:(CGFloat)newWidth
{
    CGSize imageSize = image.size;
    CGFloat width = imageSize.width;
    CGFloat height = imageSize.height;
    
   
    
    CGFloat scaledWidth = 0.0f;
    CGFloat scaledHeight = 0.0f;

    
    if (width / height > 1){
        scaledWidth = newWidth * width / height;
        scaledHeight = newWidth;
    } else if (width / height < 1) {
        
        scaledWidth = newWidth;
        scaledHeight = newWidth * height / width;
    } else {
        return image;
    }
    
    CGSize targetSize = CGSizeMake(scaledWidth,scaledHeight);
    
    UIGraphicsBeginImageContext(targetSize);

    [image drawInRect:CGRectMake(0,0,scaledWidth,scaledHeight)];
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    UIGraphicsBeginImageContext(CGSizeMake(newWidth, newWidth));
    
    [newImage drawAtPoint:CGPointMake(-(scaledWidth - newWidth) / 2.0f, -(scaledHeight - newWidth) / 2.0f)];
    UIImage* tarImg = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    
    return tarImg;
}
+ (UIImage *)fixOrientation:(UIImage *)aImage
{
    
    // No-op if the orientation is already correct
    if (aImage.imageOrientation == UIImageOrientationUp)
        return aImage;
    
    // We need to calculate the proper transformation to make the image upright.
    // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
    CGAffineTransform transform = CGAffineTransformIdentity;
    
    switch (aImage.imageOrientation) {
        case UIImageOrientationDown:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, aImage.size.width, aImage.size.height);
            transform = CGAffineTransformRotate(transform, M_PI);
            break;
            
        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
            transform = CGAffineTransformTranslate(transform, aImage.size.width, 0);
            transform = CGAffineTransformRotate(transform, M_PI_2);
            break;
            
        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, 0, aImage.size.height);
            transform = CGAffineTransformRotate(transform, -M_PI_2);
            break;
        default:
            break;
    }
    
    switch (aImage.imageOrientation) {
        case UIImageOrientationUpMirrored:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, aImage.size.width, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
            break;
            
        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, aImage.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
            break;
        default:
            break;
    }
    
    // Now we draw the underlying CGImage into a new context, applying the transform
    // calculated above.
    CGContextRef ctx = CGBitmapContextCreate(NULL, aImage.size.width, aImage.size.height,
                                             CGImageGetBitsPerComponent(aImage.CGImage), 0,
                                             CGImageGetColorSpace(aImage.CGImage),
                                             CGImageGetBitmapInfo(aImage.CGImage));
    CGContextConcatCTM(ctx, transform);
    switch (aImage.imageOrientation) {
        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            // Grr...
            CGContextDrawImage(ctx, CGRectMake(0,0,aImage.size.height,aImage.size.width), aImage.CGImage);
            break;
            
        default:
            CGContextDrawImage(ctx, CGRectMake(0,0,aImage.size.width,aImage.size.height), aImage.CGImage);
            break;  
    }  
    
    // And now we just create a new UIImage from the drawing context  
    CGImageRef cgimg = CGBitmapContextCreateImage(ctx);  
    UIImage *img = [UIImage imageWithCGImage:cgimg];  
    CGContextRelease(ctx);  
    CGImageRelease(cgimg);  
    return img;  
}

@end
